Synchronizer



Feb. 2, 1954 A.

BIXBY 2,667,955

SYNCHRONIZER Filed July 22. 1950 FIG. I

2 Sheets-Sheet 1 IN VEN TOR.

LEO A. BIXBY BY ATTYS.

Feb. 2, 1954 H L. 'A. BIXBY 2,661 955 SYN CHRON I ZER Filed July 22. 1950 2 Sheets-Sheet 2 FIG. 6

INVENTOR.

- LEO A. BIXBY BY g z ATTYS.

Patented Feb. 2, 1954 IIQD. A3 Binbti, Xiles; Mich assigmm. tm Clark: Equipment Qognpany, Budliaznam, :Miehz, &. curs poration of; Michigan Applieationdnlyfl; 1950, Serial No. 175,365.

aolaims. (cilia-539'.

Mypmsentv invention. relates to; a, clutch; and synohronizer assembly for clutohingl either of a. pair of? gears. to a. shift on which the gearsare rotatably mounted-..

In. the form; of; clutch. synchronizer: assembly, tov which my invention; is applicable; an axially slidable clutch collan member is mounted on. a splined; portions of a. shaft; on; which a pair of axially. spaced; ears: arearotatahly; mounted. The clutch collarrmember isxprovided. withujaws clutch teethwhichare adaptedito bedisnosed in engagement with jawclutch: teeth formed: Qnthe rot-at ablei gears for positivelyclutching either; one; of thea earstothe sham. Theeelutch; collar. mem: her is formed with. radially; xtending. flan e having. a plurality: of circumferentially spaced openings formed: therethmugh, whi h penin s extend. parallel, to. the; shaft: Disposed thro h the; op nin s in he flange f he lutch collar. member are-pins which; are: fixed. at. theirends in ynchronizes rings which; are adapted" tit operate withthee orementioned gears; The. pins have reduced; central portions; which define shquiderstha-t. are; adapted to cooperate with the edg efinin theonenings in the flangeot the. cl tqhcollar; member for. blocking, relatiye; axial movement of the. latter with respect. to; the. synohronizer, rings when; they are rotating asgnchronously.

Itv is an object 0,135 my; present invention. to. provide spring; loaded. mwns. between the: syn.- chronizer rings, and; the clutch collar; member, which,,upon initial. axial; movement of the latter,- willcause axial; movement of; the.- synohronizer. rings, therewith. so as. to.- dispose; one ofw the synchronizer ringsinto. clutching engagement with; the adjacent gear. and, after. synchronous speed: is reached between/the gear, and-,- clutch, collar. member, will. effect, upon further axial movement or the; clutch collar. member; snap, engagement. of, the law clutch teethof the, clutch collar member with. the, jaw clutch teeth. of thegear.

In, the; preferred. form. of my, present. invention I contemplate the provision, oi. a. plurality oi additional openings in the 'flangeof the clutoh collar. member, circumferentially spaced from. the aioredescribediopenings, and .iniwhich. former openings are disposed longitudinally. splitnpin assemblies which. are reoeivedat. their, endsrin recessesiormed inthe synchronizer. rings... The, split. pin. assemblies, are. formed, with central annular grooves which, are. biased; into engagement with, the peripheries or. the, openings in the. flange, 01 the, clutch; collar: member by resilient means disposed between the portions of'each pin" assembly: Upon initiar axi'ab movement of the clutch collar member; the-synchronizes rings fare caused to move conoiht1 y= therewith: by thesplit pin assemblies-i After-- one of the synohroni-zer rings 118134388111 disposed in clutching; engagement with the assist gear and synchronous: speedi is attained between the gear: and the. clutch oollaa: member, further: axial movement. of: the clutch collar n'lihbel willi cause-the portions ofrthez split pin= assemblies. to: compress or collapse; which cocks the latter: and effeots snapzengagementwf the jaw clutch teeth of the clutch-.oollan member with the jaw. clutch; teeth of; the; geam.

Now, in orderto: aoqua-int' those; sk-i'lledr ixr'the art with the manner ofv constructingzand: using devices in. accordanoeiwith the principles ofi my present. invention lashaili describe. in. connection with; the; accompanying-i drawings; a. preferred embodiment of; my: intention;

lnithedrawingsr Fig-111:6: L; is; a. vertioahsedtional; viewtaken through a; transmission: with: which the clutch. and synohronizerzassemblnofr mi: present inven: tinn-isgineonnoratedzz Eigureszl is: a horizontal: sentionah viewtaken. hron htherclutchz andnynchronizer assembly or. mynresent inventions;

Figure 3 is a vertical;seotionalrview;taken; along the;line 3--3-, 013 Figuref2 looking in thadirection indicated by the; arrows showing; one of. the. synchronizeltringsi; H I g N E gl e;hisam fil-zs pnfir l ewifi m a one e f flwf em nt-l o i i thedi ectiqn indioated bwthear-rows, showing the clntehmollar. embers,

Figure. 5, is. a horizontal sectional new take al a th e firfi Kismet. l i t direction: indicated by the arrows, showing 'a.

enti lrhs d-.$rl s; me l n ber-dispnsedbetween the portions. of the splitpin s-W 1; y. l

I Eignre fiiis ahoriz'ontal 's'eotifonalview similar. to-Eigurafi but S owingamodifled former my.

new f l hstervan n n shaped spring. metal clip. member disposed.

between; the portionsof, the; split. pin assembly; d

Ei gl'lr'e, 7g is? a inflammation-a1: 'view similar.

tbsF'ignresifi. andfi; but. .'showing another. modified.

rgrm a1 my intcentioni in" which. asubstantially; dumbblelkshaped resinent. member is. disppsd.

betwe n. the portions, or. the split. pin assemble Referring. now. to the.drawing is,.,there is. shown. a, transmission co' rfijst'ructioii, indieated' generally by thfe reference numeral IO' hi'eh eomprissa transmission housing H, to whioh, at the upper ing portion thereof, is suitably secured a cover member l2. A horizontally extending drive shaft |3 is journaled in a bearing assembly l4, supported in the transmission housing II, and the drive shaft |3 has an enlarged gear portion |5 formed at one end thereof within the transmission hous- One end of a horizontally extending output shaft I6 is journaled inwardly of the drive shaft |3 by means of a plurality of roller or needle bearings I6. The other end of the output shaft l6 is journaled within a ball bearing assembly l8, supported in the transmission housing I. Disposed below the output shaft l6 is a countershaft |9 which is journaled at its ends within a roller bearing assembly 26 and a ball bearing assembly 2|, supported in the transmission housing The enlarged gear portion l5 of the drive shaft I3 is disposed in meshing engagement with'a gear Rotatably 22 keyed to the countershaft l9. mounted on the output shaft I6 are gears 23, 24, and 25, which respectively have meshing engagement. with gears 26 and 21 keyed to the output shaft l9, and gear portion 28, formed integrally with the output shaft I9. Disposed concentrically about the output shaft I6, intermediate of the enlargedgear portion l5 and the rotatable gear 23, is one clutch and synchronizer assembly of my present invention, indicated generally by the reference numeral 38. A second clutch and synchronizer assembly, indicated generally by the reference numeral 3|, like the clutch and synchronizer assembly 30, is disposed concentrically about the output shaft l6, intermediate of the rotatable gears 24 and 25.

The clutch portion of the clutch and synchronizer assembly 30 comprises a clutch collar member 4| suitably mounted to the output shaft l6 for rotation therewith and adapted for axial movement therealong. The clutch collar member 4| has two sets of external jaw clutch teeth 42 and 43 which are adapted, respectively, to be selectively disposed in engagement with internal jaw clutch teeth 44 and. 45, formed integrally-with axially extending-annular flange portions 46 and 41 of the enlarged gear portion i5 and the rotatable gear 23, which flange portions 46 and 41 face the clutch collar member 4|.

The clutch collar member 4| is provided with a radially extending flange portion 48 havinga plurality of circumferentially spaced openings 49 formed therethrough, which openings 49 extend parallel to the axis of shaft l6. The edges of the openings 49 are countersunk. Disposed through alternate openings 49 in the flange portion 48 of the clutch collar member 4| are pin members 58 having central annular grooves 5| and tapered blocking shoulders 54 and 55 formed therein. Disposed through the other alternate openings 49, formed in the flange portion 48 of the clutch collar member 4|, are split pin assemblies 52 having central annular grooves 53 and tapered shoulders 53a and 531) formed therein. The split pin assemblies 52 preferably comprise semicylindrical segments, between which segments are preferably disposed substantially X- shaped spring metal clip members 54, as shown in Figure 5. The members 54 are adapted to bias the semicylindrical portions of the split pin assemblies 52 apart and normally urge the central annular grooves 53 thereof into engagement with the inner peripheral surfaces of the adjacent openings 49 formed in the flange portion 48.

The pin members 56 have reduced end portions which are rigidly secured, as by riveting, within 4 openings formed in a pair of axially spaced synchronizer ring members 56 and 51, which are formed with internal tapered friction surfaces 560. and 51a adapted to cooperate, respectively, with external tapered friction surfaces 46a and 41a formed on the axially extending annular flange portions 46 and 41 of the enlarged gear portion l5 and rotatable gear 23. Suitable circumferentially spaced recesses 58 are formed in the facing surfaces of the synchronizer ring members 56 and 51, which recesses 58 receive the ends of the split pin assemblies 52.

The clutch and synchronizer assembly 3| is identical in construction and operation to the clutch and synchronizer assembly 30. The assembly 3| comprises a clutch collar member 59 which is suitably mounted to the output shaft |6 for rotation therewith and adapted for axial movement therealong. The clutch collar member 59 is formed with two sets of external jaw clutch teeth 66 and 6| which are adapted to be disposed, respectively, in engagement with jaw clutch teeth 62 and 63 formed on the axially extending annular flange portions 64 and 65 of the rotatable gears 24 and 25, which flange portions 64 and 65 face the clutch collar member 59. The clutch collar member 59 is formed with a radially extending flange portion 66, through which a plurality of circumferentially spaced openings 12 are formed, which openings 12 extend parallel to the axis of shaft I6. The edges of the openings 12 are countersunk. Disposed through alternate openings 12 in the flange portion 66 are pin members 61 having central annular grooves 68 and tapered blocking shoulders 68a and 682) formed therein. The reduced end portions of the pin members 61 are rigidly secured, as by riveting, within a pair of axially spaced synchronizer ring members 69 and 10, which have internal tapered friction surfaces 69a and 10a adaptedto engage, respectively, with external tapered surfaces 64a. and 65a formed on the axially extending annular flange portions 64 and 65 of gears 24 and 25. Disposed through the other alternate openings 12 formed in the flange portion 66 are split pin assemblies 1|, the ends of which are received in circumferentially spaced recesses 13 formed in the facing surfaces of the synchronizer ring members 69 and 10. The split pin assemblies 1| have central annular grooves 14 and tapered shoulders 14a and 141) formed therein. The split pin assemblies 1| comprise semicyclindrical segments between which are disposed, preferably substantially X-shaped spring metal clip members which are identical to the members 54, as shown in Figure 5. The members referred to are adapted to bias the semicylindrical portions of the split pin assemblies 1| apart and normally urge the central annular grooves 14 thereof into engagement with the inner peripheral surfaces of the adjacent openings 12 formed in the flange portion 66. Journaled for axial movement in downwardly extending bosses 15 and 16, formed integrally with the transmission cover member |2, is ashift rail 11. Secured to the shift rail 11, intermediate of the bosses 15 and 16, is a shift fork 18 which is provided for effecting axial movement of the flange portion 48 of the clutch collar member 4|. Axial movement of the shift rail 11 and shift fork 18 is effected in a conventional manner by means of a shift lever 19 fulcrumed in a control tower mounted on the cover member l2. Suitable detent means, indicated generally at 8|, is provided for positioning the shift rail 11. V A second shift rail and shift fork (not showni are provided --for"effeoting* a'x-i'ai movement of th flange portion to of the clutch collar-membertfi; and are-adapted to be suitably actuated by means of theshi-ft leve'rlii.

Upon rotation o'f' thedrive shaft l3,=drive may be effected to theoutput shaft id in'one of four ratios. 'W-ith the clutch and synchronizer assembly -3 I' in a neutral position, as shown in Figure '1, axial movement of the clutch collar member 4I to the-left, from the position-showminFig- -ure- 1,- may-be'efiectedby the control lever'iS "through the shift fork' l8. tiniti'abmovement of l ertion d8. Further axial movement of the clutch collarimembei- M to the left causes the internal tapered friction surfacelisa of the synchronizer ring '56 tobe disposed into frictional engagement with the external tapered friction surface- 36a on the axially extending annular flange portion 48 of gear portion I5. Slipoccurs during initial en agement of the tapered f-riction surfaces 46a and 56a; and thus the gear I5 and synchronizer ring 56 rotate asynchronously. During this initial engagement the shoulders 54 of pins 5%) are disposed in blocking relation with respect to the edges of the adjacent openings 49 in the flange portion 48 which prevents axial movement of the clutch collar member 4| relative to the synchronizer rings 56 and 51. After the tapered friction surfaces 46a and 5611 have been fully engaged and they rotate synchronously, the shoulders 54 on pins 5| no longer block axial movement of the clutch collar member GI relative to the synchronizer rings 56 and 51.

Initial axial movement of the clutch collar member, relative to the synchronizer rings 55 and 51, causes the portions of the split pin assemblies 52 to compress or collapse which cocks the latter and effects snap engagement of the jaw clutch teeth 42 of the clutch collar member M with the jaw clutch teeth 44 on gear I5, thus providing a positive direct drive between the gear I5 and output shaft It.

In a like manner, the clutch collar member 4| may be moved axially to the right, from the position shown in Figure l, by the control lever '19 through the shift fork I8. Since engagement of the jaw clutch teeth 43 of the clutch collar member 4| is effected in the same manner as above described, it is believed that a detail description thereof is unnecessary. When the jaw clutch teeth 43 are disposed in engagement with the jaw clutch teeth 45, a second drive ratio is effected between the input shaft I3 and output shaft It.

If the clutch collar member il is returned to a neutral position, as shown in Figure l, the clutch and synchronizer assembly 3| may be shifted either to the left or to the right for effecting either one of two additional ratios between the drive shaft I3 and the output shaft I6. Since the operation of the clutch and synchronizer assembly 3| is identical to the operation of the synchronizer assembly 39, it is believed that the operation thereof will be apparent.

While the semicylindrical portions of the split pin assemblies 52 are preferably biased apart by means of substantially X-shaped spring metal clip members 54, a substantially serpentine- Shaped spring metal clip member 83 may be utilized in a modified form of my invention, as shown in Figure 6, or a substantially dumbbell-shaped assets 6 resilient member =84, as shewn in- Fi'gure-W. "it will be readilyapparent th'at the constructions shown in Fi gures 'G -and '7 maybeembodied with the split p'in assemblies! I.

Journaled on a slay shaft 85, shown2'revolvcd from its norm'al position for the sal 'ze of clarity, by'nrieams of roller or needle bearingswat, Ais a compoundgeartl having axially space portions ts' and- 89. The gear portion II- has meshing "engagement with a gear *p'c'rti'o'n formed --'integral'ly with the -counte'rshaft 18. *Mou'rited bh the output -shaft IB forv-rotation therewith-and axial movement therealong as a gear si whieh is adaptedto'be "disposed imengage'ment'with either the gear portion 89 0f compound gear izl," for effecting :reverse drivekto the cutput=sh aft Id or gear portion- 92 formed integr'ally with thecoun'tershaft I 9, for effecting-pno'the-r driveratio'to the output shaft-"15. Axial movement :of the gear SI is effected: bycm'eans of a shift: fork 93-suit'ably flxed -to an axially movableshift rail 94.

while I have shown and described what I' beli'cve to bea preferred embodiment of myzpresent invention, it will :be understood that 'va'rious modifications and rearrangementsmay be marfle therein without departing *from the spirit' and scope ofmy pre'sent invention; i

I claim: 1. For use in a transmission having a shaft and a gear rotatably mounted about the axis of the shaft and with the gear having jaw clutch teeth and a friction clutch element, the combination of a clutch and synchronizer assembly for selectively coupling the gear to the shaft comprising, a clutch collar member axially slidable on the shaft and mounted for rotation therewith adjacent the gear, said clutch collar member having jaw clutch teeth adapted to cooperate with the jaw clutch teeth on the gear, said clutch collar member having first and second openings formed therethrough parallel to the shaft, axially movable friction clutch elements one of which is adapted to cooperate with the friction clutch element on the gear, pins disposed through the first openings in said clutch collar member and rigidly connecting said axially movable friction clutch elements, means formed integrally with said pins for blocking axial movement of said clutch collar member relative said axially movable friction clutch elements when the latter and said clutch collar member are rotating asynchronously, longitudinally split pin assemblies disposed through the second openings in said clutch collar member, said axially movable friction clutch elements having recesses formed therein for receiving the ends of said split pin assemblies, and resilient means between the portions of said split pin assemblies for spring loading the latter upon initial axial movement of said clutch collar member relative said axially movable friction clutch elements for effecting snap engagement of the jaw clutch teeth of the clutch collar member with the jaw clutch teeth of the adjacent gear.

2. The combination of claim 1 wherein said split pin assemblies are formed with centrally located annular grooves normally adapted to be biased into engagement with the peripheries of the second openings in said clutch collar member.

3. The combination of claim 1 wherein said resilient means comprises substantially X-shaped spring metal clip members.

4. The combination of claim 1 wherein said resilient means comprises substantially dumbbell-shaped resilient bar members.

5. The combination of claim 1 wherein said resilient means comprises substantially serpentine-shaped spring metal clip members. v

6. For use in a transmission having a shaft and two axially spaced gears rotatably mount- -ed about the axis of the shaft and with the gears having jaw clutch teeth and friction clutch elements at the facing sides thereof,

the combination of a clutch and synchronizer assembly for selectively coupling either of the two gears to the shaft comprising, a clutch collar member axially slidable on the shaft and mounted for rotation therewith between the gears, said clutch collar member having jaw clutch teeth adapted to cooperate with the jaw clutch teeth on the gears, said clutch v collar member havin openings formed there- -through parallel to the shaft, axially movable friction clutch elements adapted to cooperate with the friction clutch elements on the gears, means rigidly interconnecting said axially movable friction clutch elements, said means being adapted to block axial movement of said clutch collar member relative to said axially movable friction clutch elements when the latter and said clutch collar member are rotating asynchronous- .ly, longitudinally split pin assemblies disposed through the openings in said clutch collar member, said axially'movable friction clutch elements having recesses formed therein for receiving the ends of said split pin assemblies, and resilient means between the portions of said spit pin assemblies for spring loading the latter upon initial axial movement of said clutch collarmember relative said axially movable friction clutch elements for effecting snap engagement of the jaw clutch teeth of the clutch collar member with the jaw clutch teeth of the adjacent gear.

LEO A. BIXBY.

References Cited in the file of thispatent UNITED STATES PATENTS Germany June 12, 1920 

